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authorH. Peter Anvin <hpa@zytor.com>2008-05-30 17:19:03 -0700
committerH. Peter Anvin <hpa@zytor.com>2008-05-30 17:19:03 -0700
commit23deb06821442506615f34bd92ccd6a2422629d7 (patch)
tree5e95dba1471007a161e19844fab2d60d422f5423 /Documentation/x86_64
parent4039feb5bae72a5fed9ba6bc1a9cfd8dfe0a8613 (diff)
x86: move x86-specific documentation into Documentation/x86
The current organization of the x86 documentation makes it appear as if the "i386" documentation doesn't apply to x86-64, which is does. Thus, move that documentation into Documentation/x86, and move the x86-64-specific stuff into Documentation/x86/x86_64 with the eventual goal to move stuff that isn't actually 64-bit specific back into Documentation/x86. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Diffstat (limited to 'Documentation/x86_64')
-rw-r--r--Documentation/x86_64/00-INDEX16
-rw-r--r--Documentation/x86_64/boot-options.txt314
-rw-r--r--Documentation/x86_64/cpu-hotplug-spec21
-rw-r--r--Documentation/x86_64/fake-numa-for-cpusets66
-rw-r--r--Documentation/x86_64/kernel-stacks99
-rw-r--r--Documentation/x86_64/machinecheck77
-rw-r--r--Documentation/x86_64/mm.txt29
-rw-r--r--Documentation/x86_64/uefi.txt38
8 files changed, 0 insertions, 660 deletions
diff --git a/Documentation/x86_64/00-INDEX b/Documentation/x86_64/00-INDEX
deleted file mode 100644
index 92fc20ab5f0..00000000000
--- a/Documentation/x86_64/00-INDEX
+++ /dev/null
@@ -1,16 +0,0 @@
-00-INDEX
- - This file
-boot-options.txt
- - AMD64-specific boot options.
-cpu-hotplug-spec
- - Firmware support for CPU hotplug under Linux/x86-64
-fake-numa-for-cpusets
- - Using numa=fake and CPUSets for Resource Management
-kernel-stacks
- - Context-specific per-processor interrupt stacks.
-machinecheck
- - Configurable sysfs parameters for the x86-64 machine check code.
-mm.txt
- - Memory layout of x86-64 (4 level page tables, 46 bits physical).
-uefi.txt
- - Booting Linux via Unified Extensible Firmware Interface.
diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt
deleted file mode 100644
index b0c7b6c4abd..00000000000
--- a/Documentation/x86_64/boot-options.txt
+++ /dev/null
@@ -1,314 +0,0 @@
-AMD64 specific boot options
-
-There are many others (usually documented in driver documentation), but
-only the AMD64 specific ones are listed here.
-
-Machine check
-
- mce=off disable machine check
- mce=bootlog Enable logging of machine checks left over from booting.
- Disabled by default on AMD because some BIOS leave bogus ones.
- If your BIOS doesn't do that it's a good idea to enable though
- to make sure you log even machine check events that result
- in a reboot. On Intel systems it is enabled by default.
- mce=nobootlog
- Disable boot machine check logging.
- mce=tolerancelevel (number)
- 0: always panic on uncorrected errors, log corrected errors
- 1: panic or SIGBUS on uncorrected errors, log corrected errors
- 2: SIGBUS or log uncorrected errors, log corrected errors
- 3: never panic or SIGBUS, log all errors (for testing only)
- Default is 1
- Can be also set using sysfs which is preferable.
-
- nomce (for compatibility with i386): same as mce=off
-
- Everything else is in sysfs now.
-
-APICs
-
- apic Use IO-APIC. Default
-
- noapic Don't use the IO-APIC.
-
- disableapic Don't use the local APIC
-
- nolapic Don't use the local APIC (alias for i386 compatibility)
-
- pirq=... See Documentation/i386/IO-APIC.txt
-
- noapictimer Don't set up the APIC timer
-
- no_timer_check Don't check the IO-APIC timer. This can work around
- problems with incorrect timer initialization on some boards.
-
- apicmaintimer Run time keeping from the local APIC timer instead
- of using the PIT/HPET interrupt for this. This is useful
- when the PIT/HPET interrupts are unreliable.
-
- noapicmaintimer Don't do time keeping using the APIC timer.
- Useful when this option was auto selected, but doesn't work.
-
- apicpmtimer
- Do APIC timer calibration using the pmtimer. Implies
- apicmaintimer. Useful when your PIT timer is totally
- broken.
-
- disable_8254_timer / enable_8254_timer
- Enable interrupt 0 timer routing over the 8254 in addition to over
- the IO-APIC. The kernel tries to set a sensible default.
-
-Early Console
-
- syntax: earlyprintk=vga
- earlyprintk=serial[,ttySn[,baudrate]]
-
- The early console is useful when the kernel crashes before the
- normal console is initialized. It is not enabled by
- default because it has some cosmetic problems.
- Append ,keep to not disable it when the real console takes over.
- Only vga or serial at a time, not both.
- Currently only ttyS0 and ttyS1 are supported.
- Interaction with the standard serial driver is not very good.
- The VGA output is eventually overwritten by the real console.
-
-Timing
-
- notsc
- Don't use the CPU time stamp counter to read the wall time.
- This can be used to work around timing problems on multiprocessor systems
- with not properly synchronized CPUs.
-
- report_lost_ticks
- Report when timer interrupts are lost because some code turned off
- interrupts for too long.
-
- nmi_watchdog=NUMBER[,panic]
- NUMBER can be:
- 0 don't use an NMI watchdog
- 1 use the IO-APIC timer for the NMI watchdog
- 2 use the local APIC for the NMI watchdog using a performance counter. Note
- This will use one performance counter and the local APIC's performance
- vector.
- When panic is specified panic when an NMI watchdog timeout occurs.
- This is useful when you use a panic=... timeout and need the box
- quickly up again.
-
- nohpet
- Don't use the HPET timer.
-
-Idle loop
-
- idle=poll
- Don't do power saving in the idle loop using HLT, but poll for rescheduling
- event. This will make the CPUs eat a lot more power, but may be useful
- to get slightly better performance in multiprocessor benchmarks. It also
- makes some profiling using performance counters more accurate.
- Please note that on systems with MONITOR/MWAIT support (like Intel EM64T
- CPUs) this option has no performance advantage over the normal idle loop.
- It may also interact badly with hyperthreading.
-
-Rebooting
-
- reboot=b[ios] | t[riple] | k[bd] | a[cpi] | e[fi] [, [w]arm | [c]old]
- bios Use the CPU reboot vector for warm reset
- warm Don't set the cold reboot flag
- cold Set the cold reboot flag
- triple Force a triple fault (init)
- kbd Use the keyboard controller. cold reset (default)
- acpi Use the ACPI RESET_REG in the FADT. If ACPI is not configured or the
- ACPI reset does not work, the reboot path attempts the reset using
- the keyboard controller.
- efi Use efi reset_system runtime service. If EFI is not configured or the
- EFI reset does not work, the reboot path attempts the reset using
- the keyboard controller.
-
- Using warm reset will be much faster especially on big memory
- systems because the BIOS will not go through the memory check.
- Disadvantage is that not all hardware will be completely reinitialized
- on reboot so there may be boot problems on some systems.
-
- reboot=force
-
- Don't stop other CPUs on reboot. This can make reboot more reliable
- in some cases.
-
-Non Executable Mappings
-
- noexec=on|off
-
- on Enable(default)
- off Disable
-
-SMP
-
- additional_cpus=NUM Allow NUM more CPUs for hotplug
- (defaults are specified by the BIOS, see Documentation/x86_64/cpu-hotplug-spec)
-
-NUMA
-
- numa=off Only set up a single NUMA node spanning all memory.
-
- numa=noacpi Don't parse the SRAT table for NUMA setup
-
- numa=fake=CMDLINE
- If a number, fakes CMDLINE nodes and ignores NUMA setup of the
- actual machine. Otherwise, system memory is configured
- depending on the sizes and coefficients listed. For example:
- numa=fake=2*512,1024,4*256,*128
- gives two 512M nodes, a 1024M node, four 256M nodes, and the
- rest split into 128M chunks. If the last character of CMDLINE
- is a *, the remaining memory is divided up equally among its
- coefficient:
- numa=fake=2*512,2*
- gives two 512M nodes and the rest split into two nodes.
- Otherwise, the remaining system RAM is allocated to an
- additional node.
-
- numa=hotadd=percent
- Only allow hotadd memory to preallocate page structures upto
- percent of already available memory.
- numa=hotadd=0 will disable hotadd memory.
-
-ACPI
-
- acpi=off Don't enable ACPI
- acpi=ht Use ACPI boot table parsing, but don't enable ACPI
- interpreter
- acpi=force Force ACPI on (currently not needed)
-
- acpi=strict Disable out of spec ACPI workarounds.
-
- acpi_sci={edge,level,high,low} Set up ACPI SCI interrupt.
-
- acpi=noirq Don't route interrupts
-
-PCI
-
- pci=off Don't use PCI
- pci=conf1 Use conf1 access.
- pci=conf2 Use conf2 access.
- pci=rom Assign ROMs.
- pci=assign-busses Assign busses
- pci=irqmask=MASK Set PCI interrupt mask to MASK
- pci=lastbus=NUMBER Scan upto NUMBER busses, no matter what the mptable says.
- pci=noacpi Don't use ACPI to set up PCI interrupt routing.
-
-IOMMU (input/output memory management unit)
-
- Currently four x86-64 PCI-DMA mapping implementations exist:
-
- 1. <arch/x86_64/kernel/pci-nommu.c>: use no hardware/software IOMMU at all
- (e.g. because you have < 3 GB memory).
- Kernel boot message: "PCI-DMA: Disabling IOMMU"
-
- 2. <arch/x86_64/kernel/pci-gart.c>: AMD GART based hardware IOMMU.
- Kernel boot message: "PCI-DMA: using GART IOMMU"
-
- 3. <arch/x86_64/kernel/pci-swiotlb.c> : Software IOMMU implementation. Used
- e.g. if there is no hardware IOMMU in the system and it is need because
- you have >3GB memory or told the kernel to us it (iommu=soft))
- Kernel boot message: "PCI-DMA: Using software bounce buffering
- for IO (SWIOTLB)"
-
- 4. <arch/x86_64/pci-calgary.c> : IBM Calgary hardware IOMMU. Used in IBM
- pSeries and xSeries servers. This hardware IOMMU supports DMA address
- mapping with memory protection, etc.
- Kernel boot message: "PCI-DMA: Using Calgary IOMMU"
-
- iommu=[<size>][,noagp][,off][,force][,noforce][,leak[=<nr_of_leak_pages>]
- [,memaper[=<order>]][,merge][,forcesac][,fullflush][,nomerge]
- [,noaperture][,calgary]
-
- General iommu options:
- off Don't initialize and use any kind of IOMMU.
- noforce Don't force hardware IOMMU usage when it is not needed.
- (default).
- force Force the use of the hardware IOMMU even when it is
- not actually needed (e.g. because < 3 GB memory).
- soft Use software bounce buffering (SWIOTLB) (default for
- Intel machines). This can be used to prevent the usage
- of an available hardware IOMMU.
-
- iommu options only relevant to the AMD GART hardware IOMMU:
- <size> Set the size of the remapping area in bytes.
- allowed Overwrite iommu off workarounds for specific chipsets.
- fullflush Flush IOMMU on each allocation (default).
- nofullflush Don't use IOMMU fullflush.
- leak Turn on simple iommu leak tracing (only when
- CONFIG_IOMMU_LEAK is on). Default number of leak pages
- is 20.
- memaper[=<order>] Allocate an own aperture over RAM with size 32MB<<order.
- (default: order=1, i.e. 64MB)
- merge Do scatter-gather (SG) merging. Implies "force"
- (experimental).
- nomerge Don't do scatter-gather (SG) merging.
- noaperture Ask the IOMMU not to touch the aperture for AGP.
- forcesac Force single-address cycle (SAC) mode for masks <40bits
- (experimental).
- noagp Don't initialize the AGP driver and use full aperture.
- allowdac Allow double-address cycle (DAC) mode, i.e. DMA >4GB.
- DAC is used with 32-bit PCI to push a 64-bit address in
- two cycles. When off all DMA over >4GB is forced through
- an IOMMU or software bounce buffering.
- nodac Forbid DAC mode, i.e. DMA >4GB.
- panic Always panic when IOMMU overflows.
- calgary Use the Calgary IOMMU if it is available
-
- iommu options only relevant to the software bounce buffering (SWIOTLB) IOMMU
- implementation:
- swiotlb=<pages>[,force]
- <pages> Prereserve that many 128K pages for the software IO
- bounce buffering.
- force Force all IO through the software TLB.
-
- Settings for the IBM Calgary hardware IOMMU currently found in IBM
- pSeries and xSeries machines:
-
- calgary=[64k,128k,256k,512k,1M,2M,4M,8M]
- calgary=[translate_empty_slots]
- calgary=[disable=<PCI bus number>]
- panic Always panic when IOMMU overflows
-
- 64k,...,8M - Set the size of each PCI slot's translation table
- when using the Calgary IOMMU. This is the size of the translation
- table itself in main memory. The smallest table, 64k, covers an IO
- space of 32MB; the largest, 8MB table, can cover an IO space of
- 4GB. Normally the kernel will make the right choice by itself.
-
- translate_empty_slots - Enable translation even on slots that have
- no devices attached to them, in case a device will be hotplugged
- in the future.
-
- disable=<PCI bus number> - Disable translation on a given PHB. For
- example, the built-in graphics adapter resides on the first bridge
- (PCI bus number 0); if translation (isolation) is enabled on this
- bridge, X servers that access the hardware directly from user
- space might stop working. Use this option if you have devices that
- are accessed from userspace directly on some PCI host bridge.
-
-Debugging
-
- oops=panic Always panic on oopses. Default is to just kill the process,
- but there is a small probability of deadlocking the machine.
- This will also cause panics on machine check exceptions.
- Useful together with panic=30 to trigger a reboot.
-
- kstack=N Print N words from the kernel stack in oops dumps.
-
- pagefaulttrace Dump all page faults. Only useful for extreme debugging
- and will create a lot of output.
-
- call_trace=[old|both|newfallback|new]
- old: use old inexact backtracer
- new: use new exact dwarf2 unwinder
- both: print entries from both
- newfallback: use new unwinder but fall back to old if it gets
- stuck (default)
-
-Miscellaneous
-
- nogbpages
- Do not use GB pages for kernel direct mappings.
- gbpages
- Use GB pages for kernel direct mappings.
diff --git a/Documentation/x86_64/cpu-hotplug-spec b/Documentation/x86_64/cpu-hotplug-spec
deleted file mode 100644
index 3c23e0587db..00000000000
--- a/Documentation/x86_64/cpu-hotplug-spec
+++ /dev/null
@@ -1,21 +0,0 @@
-Firmware support for CPU hotplug under Linux/x86-64
----------------------------------------------------
-
-Linux/x86-64 supports CPU hotplug now. For various reasons Linux wants to
-know in advance of boot time the maximum number of CPUs that could be plugged
-into the system. ACPI 3.0 currently has no official way to supply
-this information from the firmware to the operating system.
-
-In ACPI each CPU needs an LAPIC object in the MADT table (5.2.11.5 in the
-ACPI 3.0 specification). ACPI already has the concept of disabled LAPIC
-objects by setting the Enabled bit in the LAPIC object to zero.
-
-For CPU hotplug Linux/x86-64 expects now that any possible future hotpluggable
-CPU is already available in the MADT. If the CPU is not available yet
-it should have its LAPIC Enabled bit set to 0. Linux will use the number
-of disabled LAPICs to compute the maximum number of future CPUs.
-
-In the worst case the user can overwrite this choice using a command line
-option (additional_cpus=...), but it is recommended to supply the correct
-number (or a reasonable approximation of it, with erring towards more not less)
-in the MADT to avoid manual configuration.
diff --git a/Documentation/x86_64/fake-numa-for-cpusets b/Documentation/x86_64/fake-numa-for-cpusets
deleted file mode 100644
index d1a985c5b00..00000000000
--- a/Documentation/x86_64/fake-numa-for-cpusets
+++ /dev/null
@@ -1,66 +0,0 @@
-Using numa=fake and CPUSets for Resource Management
-Written by David Rientjes <rientjes@cs.washington.edu>
-
-This document describes how the numa=fake x86_64 command-line option can be used
-in conjunction with cpusets for coarse memory management. Using this feature,
-you can create fake NUMA nodes that represent contiguous chunks of memory and
-assign them to cpusets and their attached tasks. This is a way of limiting the
-amount of system memory that are available to a certain class of tasks.
-
-For more information on the features of cpusets, see Documentation/cpusets.txt.
-There are a number of different configurations you can use for your needs. For
-more information on the numa=fake command line option and its various ways of
-configuring fake nodes, see Documentation/x86_64/boot-options.txt.
-
-For the purposes of this introduction, we'll assume a very primitive NUMA
-emulation setup of "numa=fake=4*512,". This will split our system memory into
-four equal chunks of 512M each that we can now use to assign to cpusets. As
-you become more familiar with using this combination for resource control,
-you'll determine a better setup to minimize the number of nodes you have to deal
-with.
-
-A machine may be split as follows with "numa=fake=4*512," as reported by dmesg:
-
- Faking node 0 at 0000000000000000-0000000020000000 (512MB)
- Faking node 1 at 0000000020000000-0000000040000000 (512MB)
- Faking node 2 at 0000000040000000-0000000060000000 (512MB)
- Faking node 3 at 0000000060000000-0000000080000000 (512MB)
- ...
- On node 0 totalpages: 130975
- On node 1 totalpages: 131072
- On node 2 totalpages: 131072
- On node 3 totalpages: 131072
-
-Now following the instructions for mounting the cpusets filesystem from
-Documentation/cpusets.txt, you can assign fake nodes (i.e. contiguous memory
-address spaces) to individual cpusets:
-
- [root@xroads /]# mkdir exampleset
- [root@xroads /]# mount -t cpuset none exampleset
- [root@xroads /]# mkdir exampleset/ddset
- [root@xroads /]# cd exampleset/ddset
- [root@xroads /exampleset/ddset]# echo 0-1 > cpus
- [root@xroads /exampleset/ddset]# echo 0-1 > mems
-
-Now this cpuset, 'ddset', will only allowed access to fake nodes 0 and 1 for
-memory allocations (1G).
-
-You can now assign tasks to these cpusets to limit the memory resources
-available to them according to the fake nodes assigned as mems:
-
- [root@xroads /exampleset/ddset]# echo $$ > tasks
- [root@xroads /exampleset/ddset]# dd if=/dev/zero of=tmp bs=1024 count=1G
- [1] 13425
-
-Notice the difference between the system memory usage as reported by
-/proc/meminfo between the restricted cpuset case above and the unrestricted
-case (i.e. running the same 'dd' command without assigning it to a fake NUMA
-cpuset):
- Unrestricted Restricted
- MemTotal: 3091900 kB 3091900 kB
- MemFree: 42113 kB 1513236 kB
-
-This allows for coarse memory management for the tasks you assign to particular
-cpusets. Since cpusets can form a hierarchy, you can create some pretty
-interesting combinations of use-cases for various classes of tasks for your
-memory management needs.
diff --git a/Documentation/x86_64/kernel-stacks b/Documentation/x86_64/kernel-stacks
deleted file mode 100644
index 5ad65d51fb9..00000000000
--- a/Documentation/x86_64/kernel-stacks
+++ /dev/null
@@ -1,99 +0,0 @@
-Most of the text from Keith Owens, hacked by AK
-
-x86_64 page size (PAGE_SIZE) is 4K.
-
-Like all other architectures, x86_64 has a kernel stack for every
-active thread. These thread stacks are THREAD_SIZE (2*PAGE_SIZE) big.
-These stacks contain useful data as long as a thread is alive or a
-zombie. While the thread is in user space the kernel stack is empty
-except for the thread_info structure at the bottom.
-
-In addition to the per thread stacks, there are specialized stacks
-associated with each CPU. These stacks are only used while the kernel
-is in control on that CPU; when a CPU returns to user space the
-specialized stacks contain no useful data. The main CPU stacks are:
-
-* Interrupt stack. IRQSTACKSIZE
-
- Used for external hardware interrupts. If this is the first external
- hardware interrupt (i.e. not a nested hardware interrupt) then the
- kernel switches from the current task to the interrupt stack. Like
- the split thread and interrupt stacks on i386 (with CONFIG_4KSTACKS),
- this gives more room for kernel interrupt processing without having
- to increase the size of every per thread stack.
-
- The interrupt stack is also used when processing a softirq.
-
-Switching to the kernel interrupt stack is done by software based on a
-per CPU interrupt nest counter. This is needed because x86-64 "IST"
-hardware stacks cannot nest without races.
-
-x86_64 also has a feature which is not available on i386, the ability
-to automatically switch to a new stack for designated events such as
-double fault or NMI, which makes it easier to handle these unusual
-events on x86_64. This feature is called the Interrupt Stack Table
-(IST). There can be up to 7 IST entries per CPU. The IST code is an
-index into the Task State Segment (TSS). The IST entries in the TSS
-point to dedicated stacks; each stack can be a different size.
-
-An IST is selected by a non-zero value in the IST field of an
-interrupt-gate descriptor. When an interrupt occurs and the hardware
-loads such a descriptor, the hardware automatically sets the new stack
-pointer based on the IST value, then invokes the interrupt handler. If
-software wants to allow nested IST interrupts then the handler must
-adjust the IST values on entry to and exit from the interrupt handler.
-(This is occasionally done, e.g. for debug exceptions.)
-
-Events with different IST codes (i.e. with different stacks) can be
-nested. For example, a debug interrupt can safely be interrupted by an
-NMI. arch/x86_64/kernel/entry.S::paranoidentry adjusts the stack
-pointers on entry to and exit from all IST events, in theory allowing
-IST events with the same code to be nested. However in most cases, the
-stack size allocated to an IST assumes no nesting for the same code.
-If that assumption is ever broken then the stacks will become corrupt.
-
-The currently assigned IST stacks are :-
-
-* STACKFAULT_STACK. EXCEPTION_STKSZ (PAGE_SIZE).
-
- Used for interrupt 12 - Stack Fault Exception (#SS).
-
- This allows the CPU to recover from invalid stack segments. Rarely
- happens.
-
-* DOUBLEFAULT_STACK. EXCEPTION_STKSZ (PAGE_SIZE).
-
- Used for interrupt 8 - Double Fault Exception (#DF).
-
- Invoked when handling one exception causes another exception. Happens
- when the kernel is very confused (e.g. kernel stack pointer corrupt).
- Using a separate stack allows the kernel to recover from it well enough
- in many cases to still output an oops.
-
-* NMI_STACK. EXCEPTION_STKSZ (PAGE_SIZE).
-
- Used for non-maskable interrupts (NMI).
-
- NMI can be delivered at any time, including when the kernel is in the
- middle of switching stacks. Using IST for NMI events avoids making
- assumptions about the previous state of the kernel stack.
-
-* DEBUG_STACK. DEBUG_STKSZ
-
- Used for hardware debug interrupts (interrupt 1) and for software
- debug interrupts (INT3).
-
- When debugging a kernel, debug interrupts (both hardware and
- software) can occur at any time. Using IST for these interrupts
- avoids making assumptions about the previous state of the kernel
- stack.
-
-* MCE_STACK. EXCEPTION_STKSZ (PAGE_SIZE).
-
- Used for interrupt 18 - Machine Check Exception (#MC).
-
- MCE can be delivered at any time, including when the kernel is in the
- middle of switching stacks. Using IST for MCE events avoids making
- assumptions about the previous state of the kernel stack.
-
-For more details see the Intel IA32 or AMD AMD64 architecture manuals.
diff --git a/Documentation/x86_64/machinecheck b/Documentation/x86_64/machinecheck
deleted file mode 100644
index a05e58e7b15..00000000000
--- a/Documentation/x86_64/machinecheck
+++ /dev/null
@@ -1,77 +0,0 @@
-
-Configurable sysfs parameters for the x86-64 machine check code.
-
-Machine checks report internal hardware error conditions detected
-by the CPU. Uncorrected errors typically cause a machine check
-(often with panic), corrected ones cause a machine check log entry.
-
-Machine checks are organized in banks (normally associated with
-a hardware subsystem) and subevents in a bank. The exact meaning
-of the banks and subevent is CPU specific.
-
-mcelog knows how to decode them.
-
-When you see the "Machine check errors logged" message in the system
-log then mcelog should run to collect and decode machine check entries
-from /dev/mcelog. Normally mcelog should be run regularly from a cronjob.
-
-Each CPU has a directory in /sys/devices/system/machinecheck/machinecheckN
-(N = CPU number)
-
-The directory contains some configurable entries:
-
-Entries:
-
-bankNctl
-(N bank number)
- 64bit Hex bitmask enabling/disabling specific subevents for bank N
- When a bit in the bitmask is zero then the respective
- subevent will not be reported.
- By default all events are enabled.
- Note that BIOS maintain another mask to disable specific events
- per bank. This is not visible here
-
-The following entries appear for each CPU, but they are truly shared
-between all CPUs.
-
-check_interval
- How often to poll for corrected machine check errors, in seconds
- (Note output is hexademical). Default 5 minutes. When the poller
- finds MCEs it triggers an exponential speedup (poll more often) on
- the polling interval. When the poller stops finding MCEs, it
- triggers an exponential backoff (poll less often) on the polling
- interval. The check_interval variable is both the initial and
- maximum polling interval.
-
-tolerant
- Tolerance level. When a machine check exception occurs for a non
- corrected machine check the kernel can take different actions.
- Since machine check exceptions can happen any time it is sometimes
- risky for the kernel to kill a process because it defies
- normal kernel locking rules. The tolerance level configures
- how hard the kernel tries to recover even at some risk of
- deadlock. Higher tolerant values trade potentially better uptime
- with the risk of a crash or even corruption (for tolerant >= 3).
-
- 0: always panic on uncorrected errors, log corrected errors
- 1: panic or SIGBUS on uncorrected errors, log corrected errors
- 2: SIGBUS or log uncorrected errors, log corrected errors
- 3: never panic or SIGBUS, log all errors (for testing only)
-
- Default: 1
-
- Note this only makes a difference if the CPU allows recovery
- from a machine check exception. Current x86 CPUs generally do not.
-
-trigger
- Program to run when a machine check event is detected.
- This is an alternative to running mcelog regularly from cron
- and allows to detect events faster.
-
-TBD document entries for AMD threshold interrupt configuration
-
-For more details about the x86 machine check architecture
-see the Intel and AMD architecture manuals from their developer websites.
-
-For more details about the architecture see
-see http://one.firstfloor.org/~andi/mce.pdf
diff --git a/Documentation/x86_64/mm.txt b/Documentation/x86_64/mm.txt
deleted file mode 100644
index b89b6d2bebf..00000000000
--- a/Documentation/x86_64/mm.txt
+++ /dev/null
@@ -1,29 +0,0 @@
-
-<previous description obsolete, deleted>
-
-Virtual memory map with 4 level page tables:
-
-0000000000000000 - 00007fffffffffff (=47 bits) user space, different per mm
-hole caused by [48:63] sign extension
-ffff800000000000 - ffff80ffffffffff (=40 bits) guard hole
-ffff810000000000 - ffffc0ffffffffff (=46 bits) direct mapping of all phys. memory
-ffffc10000000000 - ffffc1ffffffffff (=40 bits) hole
-ffffc20000000000 - ffffe1ffffffffff (=45 bits) vmalloc/ioremap space
-ffffe20000000000 - ffffe2ffffffffff (=40 bits) virtual memory map (1TB)
-... unused hole ...
-ffffffff80000000 - ffffffff82800000 (=40 MB) kernel text mapping, from phys 0
-... unused hole ...
-ffffffff88000000 - fffffffffff00000 (=1919 MB) module mapping space
-
-The direct mapping covers all memory in the system up to the highest
-memory address (this means in some cases it can also include PCI memory
-holes).
-
-vmalloc space is lazily synchronized into the different PML4 pages of
-the processes using the page fault handler, with init_level4_pgt as
-reference.
-
-Current X86-64 implementations only support 40 bits of address space,
-but we support up to 46 bits. This expands into MBZ space in the page tables.
-
--Andi Kleen, Jul 2004
diff --git a/Documentation/x86_64/uefi.txt b/Documentation/x86_64/uefi.txt
deleted file mode 100644
index 7d77120a518..00000000000
--- a/Documentation/x86_64/uefi.txt
+++ /dev/null
@@ -1,38 +0,0 @@
-General note on [U]EFI x86_64 support
--------------------------------------
-
-The nomenclature EFI and UEFI are used interchangeably in this document.
-
-Although the tools below are _not_ needed for building the kernel,
-the needed bootloader support and associated tools for x86_64 platforms
-with EFI firmware and specifications are listed below.
-
-1. UEFI specification: http://www.uefi.org
-
-2. Booting Linux kernel on UEFI x86_64 platform requires bootloader
- support. Elilo with x86_64 support can be used.
-
-3. x86_64 platform with EFI/UEFI firmware.
-
-Mechanics:
----------
-- Build the kernel with the following configuration.
- CONFIG_FB_EFI=y
- CONFIG_FRAMEBUFFER_CONSOLE=y
- If EFI runtime services are expected, the following configuration should
- be selected.
- CONFIG_EFI=y
- CONFIG_EFI_VARS=y or m # optional
-- Create a VFAT partition on the disk
-- Copy the following to the VFAT partition:
- elilo bootloader with x86_64 support, elilo configuration file,
- kernel image built in first step and corresponding
- initrd. Instructions on building elilo and its dependencies
- can be found in the elilo sourceforge project.
-- Boot to EFI shell and invoke elilo choosing the kernel image built
- in first step.
-- If some or all EFI runtime services don't work, you can try following
- kernel command line parameters to turn off some or all EFI runtime
- services.
- noefi turn off all EFI runtime services
- reboot_type=k turn off EFI reboot runtime service